The present inventor has conducted studies for some time in order to work out a muscle development method for easy, safe, and effective muscle development, and outcomes were compiled into a patent application having Japanese Patent Application No. 5-313949, which has been granted as Japanese Patent No. 2670421.
The muscle development method according to the patent in question is a distinctive and nonconventional one that involves the application of pressure. The muscle development method (hereinafter, referred to as the “Kaatsu Training™ method”) is based on the following theoretical concept.
Muscles are composed of slow-twitch muscle fibers and fast-twitch muscle fibers. Slow-twitch muscle fibers are limited in their potential for growth. Accordingly, it is necessary to recruit fast-twitch muscle fibers of the slow- and fast-twitch muscle fibers in order to develop muscles. Recruitment of fast-twitch muscle fibers causes lactic acid buildup in the muscles, which triggers secretion of growth hormone from the pituitary. The growth hormone has effects of, for example, promoting muscle growth and shedding body fat. This means that recruitment and fatigue of fast-twitch muscle fibers results in development of fast-twitch muscle fibers and, in turn, the entire muscles.
Slow-twitch muscle fibers and fast-twitch muscle fibers are different from each other in terms of the following, Slow-twitch muscle fibers consume oxygen for energy and are recruited for low-intensity activities. On the other hand, fast-twitch muscle fibers provide for activities even when no oxygen is present. During high intense activities, the fast-twitch muscle fibers are recruited after the recruitment of the slow-twitch muscle fibers. This means that it is necessary to cause the earlier recruited slow-twitch muscle fibers to exhaust first in order to recruit fast-twitch muscle fibers.
Conventional muscle development method uses heavy exercises with, for example, a barbell to cause the slow-twitch muscle fibers to exhaust, and after which the fast-twitch muscle fibers are recruited. This approach requires a significant amount of exercises for the recruitment of the fast-twitch muscle fibers, is time-consuming, and tends to increase the burden on muscles and joints.
As an alternative approach, when doing muscle exercises with a predetermined range on the muscles near the proximal end of the limb being tightened by application of a pressure to restrict the blood flow to the distal portion from the tightened range, the slow-twitch muscle fibers which require oxygen for energy will be exhausted in a short period of time because of the reduced oxygen delivery to muscles. Thus, muscle exercises with blood-flow restriction by application of a pressure will result in recruitment of the fast-twitch muscle fibers without needing a large amount of exercises.
In addition, restriction of the blood flow by pressure application makes it hard to get the lactic acid that has built up in the muscles, out of the muscles. The lactic acid level is more likely to rise and a much larger amount of growth hormone is secreted, as compared with the case where the blood flow is unrestricted.
Based on this theoretical concept, restriction of the muscle blood flow can result in significant development of the muscles.
The Kaatsu training method is premised on the theoretical concept of muscle development by the restriction of the blood flow. More specifically, an appropriate compression pressure is applied to muscles at one or more predetermined range (s) near the proximal end of the limb to restrict the blood flow to the distal portion from the tightened range. The compression pressure puts on the muscles an appropriate load attributed to the decrease in blood flow, thereby causing muscle fatigue and, in turn, effective development of the muscles.
The Kaatsu training method has a remarkable feature of allowing muscle development without any exercises because of its mechanism of developing muscles by putting on the muscles a load attributed to the decrease in blood flow. With this feature, the Kaatsu training method is highly effective for the recovery of motor ability in people with impaired motor function, e.g., the elders or an injured person.
In addition, the Kaatsu training method can compensate for a total amount of load that is placed on the muscles by putting on the muscles a load attributed to reduced blood f low. When combined with some exercises, the method advantageously reduces an exercise-related load as compared with conventional methods. This feature produces effects of reducing possible risks of joint- or muscle-damages and shortening a necessary time period for training, because it can decrease the amount of muscle exercises for the muscle development.
It should be noted that, for the implementation of the Kaatsu training method, such a tool or device is essential that can restrict the blood flow through the muscles intended to be developed and that can precisely adjust the degree of blood flow restriction. In particular, the ability of precisely adjusting the degree of blood flow restriction in muscles is extremely important for a better effect as well as higher safety of the Kaatsu training method.
The present inventor has made studies for the Kaatsu training method and, in the course of these studies, devised an invention relating to a muscle development tool as disclosed in Japanese Patent Application No. 8-248317. The subject invention comprises a tight fitting device having a hollow band and a rubber-made pneumatic bag provided therein. Muscles are tightened and a desired compression pressure is applied thereto by introducing gas to the tube while the tight fitting device is placed around the muscles at a predetermined range.
Such type of a muscle development tool that uses gas for applying a pressure has an advantage of detailed control of the compression pressure by means of measuring the gas pressure within the pneumatic bag.
In addition, this type of a muscle development tool can vary the compression pressure to be applied to a compressed range of the limb merely by means of changing the gas pressure within the pneumatic bag. It is thus easy to vary the compression pressure with time.
The present inventor has performed the Kaatsu training using the muscle development tool of the type that uses gas to apply a pressure. During this process, the present inventor has noticed that the effects of the Kaatsu training can be improved when the compression pressure is controlled in a different manner from the one used conventionally.
Therefore, an object of the present invention is to provide a technique with which the effects of the Kaatsu training can be improved and the Kaatsu training can be expanded further.